| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent steep combustion during compression self-ignited combustion control of an engine and to satisfy a demand for reducing costs. <P>SOLUTION: When an engine 11 is driven in a compression self-ignited combustion region, a fuel injector injects a fuel into a cylinder in an NVO (negative-valve-overlap) period where an exhaust valve 23 and an intake valve 22 are both closed. Then, the fuel is injected into the cylinder in an intake stroke. The injected fuel is compressed in a compression stroke to be self-ignited. When it is determined that a steep combustion occurs and a fuel injection quantity in the NVO period is greater than a lower determination threshold (for example, minimum fuel injection quantity of a fuel injection valve 19), the fuel injection quantity in the NVO period is reduced. When the fuel injection quantity NVO is not greater than the lower determination threshold, an oxygen quantity in the cylinder in the NVO period is reduced. <P>COPYRIGHT: (C)2012,JPO&INPIT |
